Feed for power presses



Nov. 25, 1952 G. 1. DANLY Erm.

FEED FOR POWER lPRESSES 4 sheets-sheet 1 Y Filed June 9. 1948 yINVENTORS GEORGE DHA/Y BY Mfrs/L GEOEGEFF 1C) 7" TOE/VE Y Nov. 25, 1952G. l. DANLY ET AL 2,613,840

FEED FOR POWER PRESSES Filed June 9, 194s 4 sheets-sheet 2 f INVENToRsf4 TTOIQNE Y NOV. 25, 1952 1 G, DANLY ETAL 2,618,840

FEED F'OR POWER PRESSES Filed June 9, 1948 4 Sheets-Sheet 3 S M Lk;

4 Sheets-Sheet 4 YF n M THQA O n mI/Sn E tu v V.. w B

Nov. 25, 1952 G. l. DANLY ETAL FEED FOR POWER PRESSES Filed June 9. 1948mute nsum. E

Patented Nov. 25, 1952 UNITED STATES PATENT CFFICE FEED FOR POWERPRESSES nois Application fune 9, 1948, Serial No. 31,984

(Cl. :Z9-33) 14 Claims. l

Our invention relates to a feed for power presses and more particularlyto an assembly in combination with a power press for carrying the feedrolls up and down with the stock when drawing or forming operations aresuch that it is necessary to raise the stock to clear the die cavitiesbefore it is possible to feed the stock to the next operation.

Many objects are formed on power presses by means of progressive diesrequiring successive steps in which a plurality of stations are providedin a die or dies such that the stock is moved from station to station insuccessive steps.

At each station, one operation is performed. so that at the finalstation the complete object, having the desired form and shape, isfinally achieved. In operations of this character, the dies arefrequently provided with re-entrant portions and it becomes a difficultmatter to feed the stock from station to station. In operationsrequiring the raising and lowering of the stock, die designers make diesfor separate operations, each to be conducted in a different press.Stock is fed by hand and transferred from press to press, either onconveyors or by hand, and fed to succeeding presses by hand. Ourinvention permits such operations to be performed on progressive dies,using oiled stock, thus saving machinery,

conveyor equipment, man power and space.

One object of our invention is to provide a power press in whichprogressive dies formed with lre-entrant portions may be fed with stockautomatically by a double roll feed.

Another object f our invention is to provide an improved power presshaving a roll feed in which the feed rolls are carried up and down in apredetermined phased relation when drawing or forming operations aresuch that it is necessary to raise the stock to clear the die cavitiesbefore it is possible to feed the stock to the next operation.

Another object of our invention is to provide an improved power pressassembly having a roll feed in which the feed rolls are reciprocated ina predetermined timed relation to the operation of a press ram and withthe working of the die and the lift-out mechanism.

Another object of our invention is to provide a power press having feedrolls moving up and down in a predetermined timed relation and providedwith a scrap cutter whose operation is timed with the press ram and thefeed roll and lift-out movement in such manner as to provide acontinuous feeding of the stock.

Other and further objects of our invention will appear from thefollowing description.

In general our invention contemplates the provision of a frameworkadapted. to reciprocate on the press frame independently of the pressram. The framework carries a pair of feed rolls. Driving means areprovided for reciprocating the framework in timed relation to themovement of the press ram such that the stock will occupy one levelclear of the die cavities during feeding and will be in position for theforming or a drawing operation during the working stroke of the ram. Theframework carrying the feed rolls is adapted to operate the lift-outpins in the dies.

In combination with the above, we may provide if desired a scrap cutterwhich moves up and down agreeable to the movement of the stock which maybe operated by an eccentric in pre determined timed relation or whichmay be operated by the motion of the reciprocating lift-out framework.

In the accompanying drawings which form part of the instantspecification and which are to be read in conjunction therewith and inwhich like reference numerals are used to indicate like parts in thevarious views:

Figure 1 is an elevation of the press with a typical die in sectionshowing one embodiment of our invention;

Figure 2 is a side elevation taken along the line 2 2 of Figure lshowing a scrap cutter having a full width blade;

Figure 3 is a fragmentary elevation taken along the line 3 3 of Figure2, with parts in section, showing the scrap cutter drive;

Figure l is a side elevation similar to Figure 2 showing a scrap cutterof a different type 0perated by the motion of the lower lift-outrelative to the press frame;

Figure 5 is a fragmentary view taken along the line -S vof Figure lshowing details of the scrap cutter drive shown in Figure 4;

Figure 6 is a timing diagram showing the cycle of operations of thepress ram, the scrap cutter of the form shown in Figure 2 and the lowerliftout beam; that is the framework carrying the feed rolls.

More particularly, referring now to the drawings, a press frameindicated generally by the reference numeral iii supports a crown E2 onwhich is supported a prime mover such as an electric motor ifi. Themotor ill drives a flywheel !6 through a plurality 0f V-belts i8 or inany other appropriate manner. The flywheel is adapted to be clutched toand unclutched from a main driving pinion 20 as is well known in theart. The pinion 20 drives a gear wheel 22 which meshes with a gear wheel24. The gear wheel 22 drives a pinion 2S while the gear wheel 24 drivesthe pinion 28. The pinion 26 drivingly meshes an eccentric gear 30 whilethe pinion 28 drives an eccentric gear 32. The eccentrics are connectedto a, slide 34 through pitmans (not shown) as is well known in the powerpress art so that the slide is adapted to reciprocate in predeterminedtimed relation, usually with simple harmonic motion.

The slide 34 carries a slide bolster 36. The bed of the press 38 isprovided with a bed bolster 40.

In Figure 1, a six-station die is shown in which there are provided aplurality of die cushions in the slide. In the drawing, an upper lancingdie 42 is positioned between the first station which is idle and thesecond station which is idle and is provided with a die cushion 44 forstripping of stock.v At vthe third station, the upper drawing die 4G isprovided with a die cushion 48 to act as a blank holder. At the fourthstation,.an upper piercing die 50 is provided with a die cushion 52 forstripping of stock. At the fth station, an upper redrawing die 54 isprovided with a die cushion 56. At the sixth station, an upper trimmingdie 58 is provided with a die cushion 60. On the bed bolster 40, a lowerdie, or dies, is positioned upon the bed bolster 40 for cooperation withthe corresponding and co-acting upper dies.

A pair of gear boxes 62 and 64 are carried by the crown of the press. Agear 66 meshes with eccentric gear 30 for rotation thereby and a gear 68is rotatedV from eccentric gear 32. A gear 'I0 is housed within the gearbox S2 and meshes with a pinion I2 driven by gear 66. A pinion '4 isadapted to rotate with gear 68 and meshes with gear 15 housed Withingear box 64. The power ranges are such that the shaft Tl, carrying thecam T8, will rotate at the same speed as the gear 3! and the cam 80 willrotate at the same speed as the gear 32. A pair of cams 'i8 are adaptedto be driven by the rotation of gear 10. A pair of cams 80 are adaptedto be driven through gear 16. A pair of levers 82 are pivotally securedto a pair of lugs 84 carried by the press crown. A pair of lever 36 arepivotally secured to lug 88 secured to the crown of the press |2. Theends of levers 82 are bifurcated and pivotally connected to a pair ofsupporting rods 90, the lower ends of which are pivotally secured tolugs S2 carried by a feed roll-supporting framework 94. The lever 82 areprovided with a pair of cam followers 96 engaging respective cams '13.The arrangement is such that the rotation of cams 13 will move theroll-supporting framework 94 up and down with a motion depending uponthe shape of the cam. The cams 'I8 are secured to a shaft TI forrotation therewith. The shaft TI operates a Shaper motion lodged withinhousing S adapted to reciprocate member 99 to which a rack |00 isconnected, rotating a drive pinion secured to a shaft |02 adaptedthrough intermeshing bevel gears to rotate the drive shaft |04 throughan overrunning clutch as is well known to the art. The rotation of thedrive pinion through the rack |00 also rotates connecting shaft |06,rotating roll feed drive shaft |08 through a pair of bevel gears 0. Thedrive shaft |04 is splined to sleeve ||2 such that the sleeve mayreciprocate relative to the drive shaft |04. Rotation of the sleeve ||2will operate the feed rolls ||4 and H5 through gears in gear box H3. Theupper position of the feed rolls is shown by ref- 4 erence numerals ||4and I5. The lower posi' tion of the feed rolls is shown by the referencenumerals ||4a and ||5a.

Similarly the lower end of roll feed drive shaft |08 is housed in asplined sleeve ||6 such that the sleeve ||6 may reciprocate relative tothe drive shaft |08 and drive the feed rolls ||8 and ||9 throughappropriate gearing. The upper position of the feed rolls driven by theshaft |08 is shown by the reference numerals ||8 and IIS. The lowerposition of the feed rolls is shown by the reference numerals ||8a and|I0a.

The levers 86 carry cam followers |20 similar to cam followers 96. Theends of levers 06 support a pair of tension rods |22 similar to tensionrods 90. The lower ends of rods |22 are pivotally secured to a pair oflugs |24 carried by the roll feedsupporting framework 94. A lift-out bar|26 is likewise carried by the framework and adapted to reciprocate withit.

The bed bolster carries a die 4| intermediate the idle rst station andthe idle second station adapted to cooperate with the upper lancing die42. The bed bolster 40 carries a die 45 adapted to cooperate with theupper drawing die 46 at the third sta-tion. The lower die is providedwith a stripper pad |28. Stripper pins |30, adapted to be actuated bythe lower lift-out bar |26, contact the lower surface of the stripperpad |28. A lower piercing die 49 cooperates at the fourth station withthe upper piercing die 50 and is provided with a stripper pad |32, thelower surface of which contacts stripper pins |34, adapted to beactuated by the lower lift-out bar |26. At the fifth station, we providea lower redrawing die 53 adapted to cooperate with the upper redrawingdie 54. The lower redrawing die 53 is provided with a stripper pad |36,the lower surface of which is in contact with stripper pins |38, adaptedto be actuated by the lower lift-out bar |26. At the sixth station, weprovide a trimming die 57 adapted to co-act with the upper trimming die58, the finished piece adapted to drop as shown-by the dotted-lineposition and the arrow. It is-to be understood of course that anydesired die arrangement may be used, the particular die arrangementshown being for purposes of illustration only and not by way oflimitation.

In Figure l, the stock enters the initial feeding rolls ||8 andv |9 andis fed to the .left by the conjoint action of rollsl |8 and ||9 andlrolls ||4 and ||5 which are moved in timed relation by a common drivewhile the rolls are in the upper position shown by the line indicatedbythe reference numeral |40. The stock in the process of being formed isin the position indicated by the reference numeral |42 during .theworking part of the cycle. The stock material, after the` shapes beingpressed in the presshave been trimmed from the sheet, moves to the leftand comes into contact with a scrap cutter.

In the form of the scrap cutterV shown in Figures 2 and 3, an eccentric|44 is'secured tov shaft 'H which is rotated by the gear 10 meshing withpinion 12. Rotation of the eccentric reciprocates a pitman |46 securedthereto in. predetermined timed relation. The lower end of pitman |46 issecured to a connecting member |48 carried in a housing |50. The member|48 is provided with a screw |52, the position of which is adjusted bynut |54, the periphery of which is provided with a worm gear cooperatingwith a worm |56. The worm |56 is rotated by hand Wheel |58 and isadapted to adjust a blade holder 6,0 to which the upper cutting blade|162 is secured. The blade holder |60 is adapted to reciprocate in apair of guides |64. The lower blade |66 is carried by the frame 93 whichis fastened to the bed of the press. The operation of the scrap cutteris timed so that the scrap is cut after the feeding motion has takenplace and the feed is in the lowermost position.

In the form of the invention shown in Figures 4 and 5 where the scrapcomprises strips at each edge of the stock, the scrap cutter need notextend the full width as shown in Figures 2 and 3. In such a case, thescrap cutter may be operated by the motion of the roll-carryingframework.

Referring now to Figure 4, the scrap cuttel comprises a pair of lowerblades which are fixed to the reciprocating roll-carrying framework 94.The press frame I0 carries a pair of lugs |12, each having an adjustablescrew |74. The upper blades of the scrap cutters |16 are pivoted. As thelifting rods 90 and |22 move the framework carrying the rolls ||4 and||5 upwardly, rollers |78 carried by extensions of the upper blades |16engage the screws |14 so as to pivot the upper blades to open position,thus insuring that the cutters are in open position during theroll-feeding movement. While in this position, the roll-feeding drivemechanism operating through drive shaft |04 and splined sleeve ||2 andassociated gearing rotate the feeding rolls I|4 and ||5 to move thestock being fed through a predetermined distance. A lower pair of lugs|86 carried by the press frame carry adjustable screws |82. As theroll-carrying framework moves downwardly, the screws |82 will engagerollers |78 to pivot the upper blades |16 to closed position, thuseffecting the cutting of the scrap. This type of scrap cutter is adaptedonly for operations using one width of stock. If different widths ofstock are to be used, a scrap cutter running the entire width of therolls is preferred.

In operation, the stock |42 is threaded to the second station and thepress sei-l into operation. The cams 7S and 80 will move about 140 fromthe position shown in Figure l, permitting the stock to lie over thelower die. The press completes its cycle and the lancing die 42 willlance the end of the stock at a point between the first and secondstations which are idle. As the cycle continues, the cams 'i8 and 80will return to the position shown in Figure 1 and pull rods 94| and |22will lift the framework upwardly to move the stock and the feeding rollsto the level shown by construction line |40 in Figure 1. While the stockis in this position, the roll-feeding mechanism will be actuated torotate the rolls just sufficiently to move the end of the stock onestation. The end of the stock is now in the third station and the dies46 and 45 will cooperate to perform the rst draw. As the cams again liftthe rollcarrying framework and the lower lift-out bar |26 upwardly, thestripper pins |30 will move the blank holding pad |28 upwardly to movethe stock again to the position level of the construction line |40 sothat the cupped portions are clear of the re-entrant portions of thedie. In this position, the feeding rolls are again operated by the rollfeeding mechanism to roll the stock through one station, bringing afresh portion of the stock to the third station and moving the stockwhich formerly occupied the third station to the fourth station. rIhecycle of the press then continues to lower the stock to the die surfaceby the operation of cams '|8 and 80. The press drive train operates thepress slide and the upper bolster seats the upper dies into theirco-acting lower dies. At the third station, the first draw is againperformed on a fresh section of the stock while at the fourth stationdie 50 cooperates with die 49 to pierece the stock which has beensubjected to the first draw. As the two pairs of cams i8 and 8i) movethe draw bars 9 and |22 upwardly, the roll-carrying framework movesupwardly, together with the lower lift-out bar |26. The stripper pins|30 move the pad |28 0f the die 45 upwardly and the stripper pins |34move the stripper pad |32 upwardly so that the cups at the third andfourth stations are moved out of the lower dies to the level indicatedby the construction line |40 along with the feeding rolls. While thefeed roll-carrying framework and the lower lift-out bar are dwelling inthe upper position, the roll-feeding mechanism is again operated to movethe stock to the left, as viewed in Figure l, through one station. Freshstock is now brought to the first draw, the portion of the stocksubjected to the rst draw is brought to the fourth station for action bythe piercing dies and the stock which has been subjected to the rst drawat the first station and pierced at the fourth station is now inposition at the fifth station. The continuation of the cycle drops thefeed roll-carrying framework and the lift-out bar, permitting the stockto move to the position shown in full lines in Figure 1. At the fifthstation, the stock is subjected to a redrawing operation by theco-action of dies 53 and 54, dies 5|] and 49 cooperating to pierce, anddies 45 and it cooperating to perform the first draw. When the feedroll-carrying framework is again moved upwardly, not only do thestripper pins |3 and |34 operate but the stripper pins |38 co-act withthe stripper pad |36 to lift the stock subjected to the redrawingoperation at the fifth station so that all of the stock and the feedrolls is lifted clear of the lower dies. While the stock dwells in thisposition, the feed rolls again operate to move the stock to the leftthrough another station. This brings the stock occupying the position atthe third station to the fourth station, that occupying the fourthstation to the fifth station and that occupying the fifth station to thesixth station. The cycle is again performed by the press and the stockat the sixth station is trimmed by the co-acting trimming dies 51 and 58so that the formed part drops as shown by the arrow. Another cyclebrings the end of the stock to the feed rolls ||4 and ||5 which areoperated by a drive mechanism in common with the drive mechanism forfeed rolls H3 and H9. The stock will then move step-by-stepwise withoperations between movements to the left. Just after the stock has beenadvanced while in the upper period of dwell of the roll-carryingframework, the eccentric which drives the scrap cutter moves the pitman|46 and the upper blade |62 downwardly to cut the end of the used stockinto a strip of scrap.

The scrap cutter has a long stroke so that the blade |62 is above thestock while the stock is being fed and moving down. At about of theeccentric gear motion, the downward motion stops. The scrap cutter bladecontinues downwardly and cuts oir the scrap.

The timing of the motions of the slide, the scrap cutter and the lowerlift-out in a typical case is shown in Figure 6.

In the form of the invention shown in Figure 5, the upper adjustingscrews |74 insure that the blades are open during the period in whichthe roll feed operates to feed the stock through the predetermineddistance. As the draw rods permit the roll-carrying framework to movedown wardly the lower adjusting screws |82 operate the upper scrapcutting blades H6 to cut the scrap.

It will be seen that we have accomplished the objects of our invention.We have provided a power press in which progressive dies formed withre-entrant portions may be fed with stock material automatically by adouble roll feed in which the feed rolls are carried up and down in apredetermined timed relation. The stock is thus carried clear of the diecavities during the period in which the stock is fed for the nextoperation. The roll-carrying framework is reciprocated in phasedrelationwith thepress slide and with the operation of the die lift-outmechanism. We have-provided a power presshaving a roll feed moved to aposition clear of the die cavities during the feeding of the stock incombination with the scrap cutter whose operation is timed with thepress ram feeding rolls and liftout movement in such manner as toprovide a continuous feeding of the stock with the cutting ofthe ends ofthe used stock into scrap.

It will be understood that certain features and subcombinations are ofutilityl and may be employed without reference to other features andsubcombinations. This is contemplated byv and is within the scope of ourclaims. It is further obvious that various changes may be made indetails within the scope of our claims without departing fromrthe spiritof our invention. It is therefore to be understood that our invention isnot to be limited-to the specific details shown and described.

Having thus described our invention what we claim is:

1. In aipower press, a slide, a bed bolstery driving means forreciprocating said slide, means adapted to support a die on the bedbolster, means adapted to support a co-acting die for cooperation withthe die carried by the bed bolster, 4a movable fra-me, stock-feedingrolls carried by saidframe, means drivingly connecting said frame tosaid slide-driving means for reciprocating said frame vertically inpredetermined timed relation with said slide, and means driven from saidslide-driving means for operatingV saidfeeding rolls in predeterminedphasedl relationwith the movement of `said feed rollcarrying frame.

2. Inla power press, al slide, a bed bolster, driving.l means forreciprocating said slide, means adaptedv to support a die on the bedbolster, meansadapted to support a co-acting die for cooperation withthe die carried by the bed bolster, a movable frame, stock-feeding rollscarried by said frame, means drivingly connecting said vframe to saidslide-driving means for reciprocating said frame vertically inpredetermined timed relation with said slide, Vmeans driven from saidslide-driving means for operatingvsaidV feeding rolls in predeterminedphased relation with the movement of said vfeed rollcarrying frame, saiddie .carried by the bed bolster being provided with a 'lift-out pin, alift-out .bar carried by said frame for operating said lift-out piny thearrangement being `such that when the frame is moved upwardlythefstock-feeding rolls and the lift-out pin will raise Vthe kstockito alevel clear of the bed die.

3. In a power press, a slide,;a bed bolster, driving means forreciprocating saidV slide, Vmeans adapted to support a diecn thev bedbolster,

means adapted to support a co-acting die for cooperation with the diecarried by the bed bolster, a movable frame, stock-feeding rolls carriedby said frame, means drivingly connecting said frame to saidslide-driving means for reciprocating said frame vertically inpredetermined timed relation with said slide, means driven from saidslide-driving means for operating said feeding rolls in predeterminedphased relation with the movement of said feed rollcarrying frame, ascrap cutter carried by said frame, and means for actuating said scrapcutter from said slide-drivingmeans in predetermined timed relation withthe movement of said slide and said frame.

4. In a power press, a slide, means for reciproeating said slide, aprime mover for driving said slide-reciprocating means, a movableframework carried by the power press for reciprocal movement relative tosaid slide, means driven from said slide-driving means for reciprocatingsaid framework vertically in predetermined timed relation with themovements of said slide, a pair of stock-feeding rolls carried by saidframework, means driven from said slide-driving means for operating saidstock-feeding rolls in predetermined timed relation with the movement ofsaid framework, the construction being such that said feeding movementwill occur while said framework is in a raised position whereby thestock may be fed in a raised position.

5. A power press as in claim 4 including in combination a bed bolster, aslide bolster carried Aby said slide, co-acting dies carried by theslide bolster and the bed bolster, a lift-out bar carried by saidframework, stripper pins associated with said bed bolster diesactuated'by said lift-out bar whereby the stock is moved to raisedposition by said stock-feeding rolls and said stripper pins.

6. A power press as in claim 4 including in combination a scrap cutterhaving at least one blade carried by said framework, means rdriven fromsaid slide-driving means for actuating said scrap cutter inpredetermined timed relation.

7. A power press as in claim 4 including in combination a scrap cuttercarried by said frame'- work and means for operating said scrap cutteras a function of the movement of said framework.

8; A power press as in `claim l4in which said stock-feeding rollscompriseV two pairs of rolls positioned on each side of the slide.

9. A power press as in claim 4 in which said means driven from saidslide-driv-ing means for reciprocating said framework includes'a pair ofshafts, respective gears secured to said shafts each meshing with a gearof a gear train for reciprocating said slide, a pair lof cams secured torespective shafts for rotation therewith, and draw bars actuated by said.shafts secured to said framework.

10. A power press as in claim 4 in which said means driven from saidslide-driving means for reciprocating said framework includes a .pair ofshafts, respective gears secured to said shafts each meshing with a gearof a'gear train for reciprocating said slide, a pairof cams secured torespective shafts for rotation'therewith, a pair of levers pivoted tothe'press, cam followers adapted to be actuated by said cams' carried bysaid levers intermediate their ends and draw bars extending from theends of said levers to said framework.

11. A power press as inclaim 4 in which said means Adriven from theslide-driving means for operating the stock-feeding rolls includes ashaft, a gear secured to said shaft for rotation therewith, said gearmeshing with the gear of the gear train for reciprocating said slide, arack, means actuated by the rotation of said shaft for reciprocatingsaid rack, a pinion, and overrunning clutch means connecting said pinionto a roll feed drive shaft.

12. A power press as in claim 4 in which said means driven from theslide-driving means for operating the stock-feeding rolls includes ashaft, a gear secured to said shaft for rotation therewith, said gearmeshing with the gear of the gear train for reciprocating said slide, arack, means actuated by the rotation of said shaft for reciprocatingsaid rack, a pinion, overrunning clutch means connecting said pinion toa roll feed drive shaft, said drive'shaft including a section permittingrelative movement longitudinally of the drive shaft while preventingrelative rotational movement between said section and the shaft, theconstruction being such that the feed rolls may reciprocate relative toone portion of the feed roll drive shaft.

13. A power press as in claim 4 including in combination a scrap cutterone blade of which is carried by said framework, a second blade adaptedto co-act with said first blade, means for mounting said second -bladefor reciprocal movement relative to the press frame, said means forreciproeating said framework including a shaft, means to rotate saidshaft from the driving train for reciprocating said slide, an eccentriccarried by said shaft, and a pitman connecting said eccentric to saidsecond blade for reciprocating it in predetermined timed relation to themovement of the press slide.

14. A power press as in claim 4 including in combination a scrap cutterone blade of which is carried by said framework, a second blade adaptedto co-act with said first blade, means for mounting said second bladefor reciprocal movement relative to the press frame, said means forreciprocating said framework including a shaft, means to rotate saidshaft from the driving train for reciprocating said slide, an eccentriccarried by said shaft, a pitman connecting said eccentric to said secondblade for reciprocating it in predetermined timed relation to themovement of the press slide, and means for adjusting the position ofsaid second blade whereby to vary the ambit of its travel.

GEORGE I. DANLY.

VASIL GEORGEFF.

REFERENCES CITED The following references are of record in the file ofthis patent:

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